Indian, US scientists identify a black hole that spins near maximum possible rates

US and Indian scientists have jointly found a black hole in the binary star system 4U 1630-47 that spins close to the maximum possible rate.  They used India’s first dedicated astronomy satellite, AstroSat, and NASA’s Chandra X-ray Observatory.  Gravity of the core is so strong that the star’s entire mass is crushed into a point.

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